Ketchup can be used in lots of dishes too...It can be combined with other things to make nice spicy sauces, glazes, etc... Sure mustard is good from a culinary standpoint...it goes well in specialty macaroni dishes, it can be mixed with honey or spices to manipulate the taste, and I hear it goes well on lamb. Both are good, but I'm a ketchup addict...I can even stand to drink it...who would have thought that a mix of tomato paste, vinegar, and onion powder could be so great? It goes on almost anything...I don't go a day without smothering my dinner in ketchup.